This invention relates to database management systems. More specifically, the invention is concerned with ensuring integrity of a database.
It is well known to perform periodic dumps of a database, and to maintain a journal file, recording changes that have been made to the database since the last dump. Then, if a failure occurs, causing loss of information in the database, the database can be reconstructed by taking the last dump, and rolling it forward by applying the changes in the journal file.
A problem with this is that rolling the database forward can take a long time. Moreover, it usually has to be done when time is at a premium, when the recovery is taking place after a crash.
The object of the present invention is to provide a way of overcoming this problem.